No. 2 — Feb. 22, 2021


Primary Bud Mortality of Selected Cultivars

On Monday Feb. 22, 2021, cane samples were collected from four different vineyard blocks in the vicinity of Hermann, Mo. Approximately 50 buds were evaluated for each sample on Feb. 24-25. Two samples of Vignoles had the greatest bud damage (Table 1). As I mentioned in the previous report, a number of factors play a role in bud mortality, including location. Bud mortality of Vignoles was 5% and Chambourcin was 18% at the Missouri State Fruit Station in Mountain Grove, Mo (Table 2). Almost the exact opposite results compared to Gasconade County. Wright county (Mountain Grove, MO) did experience lower temperatures compared to the east-central area where Gasconade and Franklin counties are located (Figure 3). The bud mortality data from Mountain Grove suggests that growers should definitely determine bud mortality of Chardonel and Vidal blanc.

In summary, from this limited data set from Gasconade, Franklin and Wright counties the below zero temperatures that occurred on Feb. 13-16, 2021, resulted in very limited damage to grape buds.

Table 1. Primary bud mortality of selected grape cultivars from four different vineyard blocks located in Gasconade and Franklin counties, Missouri.

Sample no. Location Cultivar Primary bud
mortality (%)
1 Franklin County Vignoles 6
2 Gasconade County Vignoles 22
3 Gasconade County Vignoles 24
4 Franklin County Chambourcin 2
5 Gasconade County Chambourcin 2
6 Gasconade County Chambourcin 4
7 Gasconade County Vincent 4
8 Gasconade County Norton 6
9 Gasconade County Concord 3

Table 2. Primary bud mortality of selected grape cultivars at the Mountain Grove Fruit Station in Wright County, MO. Data supplied by Marilyn Odneal

Sample no. Location Cultivar Primary bud
mortality (%)
1 Wright County Cayuga white 1
2 Wright County Chambourcin 18
3 Wright County Chardonel 29
4 Wright County Norton 3
5 Wright County Seyval blanc 5
6 Wright County Traminette 21
7 Wright County Vidal blanc 34
8 Wright County Vignoles 5

Map of Missouri with county names labeled, and the lowest reported Feb. 16, 2021 temperatures for the state indicated by county. Labels from north to south--Achison: -26.2; Buchanan: -13.9; Linn: -12.6; Monroe: -12.9; Lafayette: -14.6; Boone: -10.8; Lincoln: -6.7; Bates: -15.6; Morgan: -14.9; Craword: -7.8; Lawrence: -16.1; Wright: -12.4; Shannon: -7.8; Cape Girardeau: -4.9
Figure 3. The lowest recorded air temperatures for 2021 occurred in Missouri on Feb. 16, 2021. Most counties experienced below zero temperatures for the period of Feb. 13-16, 2021. Data from